[HBASE-21072] Block out HBCK1 in hbase2

• Type: Sub-task
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.0.1
• Fix Version/s: 3.0.0-alpha-1, 2.2.0, 2.1.1, 2.0.2
• Component/s: hbck
• Hadoop Flags: Reviewed

Release Note

Fence out hbase-1.x hbck1 instances. Stop them making state changes on an hbase-2.x cluster; they could do damage. We do this by writing the hbck1 lock file into place on hbase-2.x Master start-up.

To disable this new behavior, set hbase.write.hbck1.lock.file to false

• Assignee: Michael Stack
• Reporter: Michael Stack
• Created: 19/Aug/18 10:55
• Updated: 20/Sep/18 18:31
• Resolved: 27/Aug/18 13:08

Description

busbey left a note in the parent issue that I only just read which has a prescription for how we might block hbck1 from running against an hbase-2.x (hbck1 could damage a hbase-2....Its disabled in hbase-2 but an errant hbck1 from an hbase-1.x install might run).

Here is quote from parent issue:

I was idly thinking about how to stop HBase v1 HBCK. Thanks to HBASE-11405, we know that all HBase 1.y.z hbck instances should refuse to run if there's a lock file at '/hbase/hbase-hbck.lock' (given defaults). How about HBase v2 places that file permanently in place and replace the contents (usually just an IP address) with a note about how you must not run HBase v1 HBCK against the cluster?

There is also the below:

We could pick another location for locking on HBase version 2 and start building in a version check of some kind?

... to which I'd answer, lets see. hbck2 is a different beast. It asks the master to do stuff. It doesn't do it itself, as hbck1 did. So no need of a lock/version.

Issue Links

• links to: Review Board (branch-2.0)